Prostate cancers initially need the male hormone testosterone for growth. Hormone therapies that lower the level of testosterone are among the most effective treatments for prostate cancers that have spread to other organs (metastasized). Over time, however, many prostate cancers continue to grow despite hormonal therapies (“castration-resistant” prostate cancer). Some prostate cancers have features called “neuroendocrine markers” which do not respond well to hormonal therapies or other therapies that are used to treat typical advanced prostate cancer.
The purpose of this study is to evaluate the safety and effectiveness of an investigational drug called MLN8237 in men with metastatic castration-resistant prostate cancer with neuroendocrine features. MLN8237 works by blocking aurora kinase, an enzyme that helps cancer cells divide and reproduce. MLN8237 is a pill that is taken by mouth.